\(P=A+B\)
\(P=\dfrac{2\sqrt{x}}{\sqrt{x}+2}+\dfrac{3\sqrt{x}}{\sqrt{x}-2}-\dfrac{5x+4}{x-4}\)
\(P=\dfrac{2\sqrt{x}\left(\sqrt{x}-2\right)+3\sqrt{x}\left(\sqrt{x}+2\right)-5x-4}{\left(\sqrt{x}+2\right)\left(\sqrt{x}-2\right)}\)
\(P=\dfrac{2x-4\sqrt{x}+3x+6\sqrt{x}-5x-4}{\left(\sqrt{x}+2\right)\left(\sqrt{x}-2\right)}\)
\(P=\dfrac{2\sqrt{x}-4}{\left(\sqrt{x}+2\right)\left(\sqrt{x}-2\right)}\)
\(P=\dfrac{2\left(\sqrt{x}-2\right)}{\left(\sqrt{x}+2\right)\left(\sqrt{x}-2\right)}\)
\(P=\dfrac{2}{\sqrt{x}+2}\)
Với `x >= 0,x \ne 4` có:
`P=A+B=[2\sqrt{x}]/[\sqrt{x}+2]+[3\sqrt{x}]/[\sqrt{x}-2]-[5x+4]/[x-4]`
`P=[2\sqrt{x}(\sqrt{x}-2)+3\sqrt{x}(\sqrt{x}+2)-5x-4]/[(\sqrt{x}+2)(\sqrt{x}-2)]`
`P=[2x-4\sqrt{x}+3x+6\sqrt{x}-5x-4]/[(\sqrt{x}+2)(\sqrt{x}-2)]`
`P=[2\sqrt{x}-4]/[(\sqrt{x}+2)(\sqrt{x}-2)]`
`P=[2(\sqrt{x}-2)]/[(\sqrt{x}+2)(\sqrt{x}-2)]`
`P=2/[\sqrt{x}+2]`
